Fabricated centrifugal pump



Jan. 9, 1951 w. H. PFARRER FABRICATED CENTRIFUGAL PUMP 3 Sheets-Sheet 1Filed Sept. 4, 1948 ATTORNEY5 Jan. 9, 1951 w. H. PFARRER FABRICATEDCENTRIFUGAL PUMP 3 Sheets -Sheet' 2 Filed Sept. 4, 1948 INVENTOR BY WWATTORNEYJ.

W. H. PFARRER FABRICATED CEN'I'RIFUGAL PUMP Jan. 9, 1951 3 Sheets-Sheet5 Filed Sept. 4, 1948 i innlinn==s nNvEN-roR W BY *5? ATTORNEYS PatentedJan. 9, 1951 UNIT E D STATES PATENT O F Fl CE FABRICATED OENTRIFUGALPUMP William H, Pfarrer, Baldwinsville, N. Y assig'nor" to MorrisMachineWorks, Baldwinsville, N. Y.,. a; corporation of New York Application;September 4, 1948, Serial No. 47,932-

1 Claim. 1.

This invention relates toa' centrifugal pump and more particularly, to apumpof this type which is constructed mainly of members whicharefabricated of flat sheet or rolled metal and areconnectediwith oneanother" by, welding, such members being generally, known in theindustry as Weldments.

Heretofore the main members of such pumps have-been made of castmetalwhich necessitated makingpatterns foruse'in producing the molds inwhich these members were cast, which operation involvesconsiderableexpense: The'production of 'the" pumps in this manner. alsorequires considerable machining for the" purpose of fin ishing the partsbefore they can" be "used.

One of'the objectsof thisinvention' is toprovide-a centrifugal pump; theprincipal members of which are constructed from metal sheets or 'thelike which have been rolled'and from which these'members-can he cut bymeans of a flame orthe like and'connected with each other partly bywelding and partly by means of bolts or similar means, thereby enablingthe pump tobe manufactured and assembled with a minimum of machining anda so permittingthe'several parts of the pump to be easily andconveniently assembled" and" d sassembled" forinspection, ad'- justmentand repairing;

A. further object of this? invention" is" to so organize a pump 'of.this character that the interior of-the samemaybe readily provided witha protecting lining, such: as rubber, metal or thedike; foruse inpu-mping'liquidscontaining abrasives and also liquids: of -acorrosivecharac-;- ter, some of. thesehning; members-also: serving as" gasketsforproducing leakfetight jointsbe tween the members of the pump-casing;

In the-accompanying drawings:

Fig. Lis aside elevat on? of a centrifugal pump embodying theseimprovements.

Fig; 2 is. an elevationof thesamei viewed from the front end thereof.

Fig.1 3 is a fragmentary vertical longitudinal section,. on an enlargedscale;..taken .on line'3-3, Fig. 2;

Figs; 4 anda5:areverticalicrossusections; on a reduced scale; taken onthe correspondingly numbered-lines ofFig.. 3." 1 Fig; 6 is a horizontalsection taken on'line.-6--6,- Fig. 4.

In-thefollowing: description similar characters .ofLreference indicatelikepartsin the sev-. eral figures of; the drawings I The numeral l8represents. thebase; of the mainframe J01": the;. pump which-may; be aof any 2i suitable constructionrand which is provided on the upper sideof. its front and rear ends-with front and rear standards ll, [2. Thetops of these standards are" provided; respectively, with frontand rearbearings l3, [4 in which is journaled a horizontallongitudinaldriving'sh'aft l5 which forms part of the means foroperatin'g the pump;This shaft may be driven by. power derived from any suitable source.

In general the pump proper of this invention comprises a casing whichcontains a pressure chamber l 6' havingvthe form of a volute, an inleteye I! arranged centrally on the front side of this chamber and axiallyin line with the driving shaft, andan outlet spout lilextending tangentially from a peripheral part of the pressure chamber, and a rotaryimpeller or runner arranged within the pressurechamberand mounted onthe-front end of the driving shait'and adapted to draw the fluid'to bepumped axially inward through the inlet eye lT'into the pressure chamher It, rotatethe'same circumferentially within the latter and thendischarge it tangentially therefrom through the peripheral outlet l8. v

The main members which form the enclosure or housing of theca'singinclude a circumferenti'al wall; a front transverse sidewalland'a rear transverse sidewall. The circumferential wall of the pressurechamber is preferably made from a bar or stripof weldable metal which isrolled. so thatit: is channel shape-or U-shape'in cross section" andbent so as to form a peripheral wall I 9 whichisof'substantially"cylindrical shape but is open or'split'at'on'e partthereof and terminates at itsendson opposite sides ofithis split'in twotangentialwingszll; 21 which are spaced: apart transversely and formitwolongitudinal wall sections of the enclosure constituting the tubularoutletspout I8 oithescasing, as shown iniFig'; 4. At its front'and'rearedges this periph eral wall of'the'pressurechamber is provided withoutwardly projecting 'fianges 22; 23' and" at their front and rear edgesthe outlet'spout walls 20', 2 l are provided with outwardly projectingcoupling fiangesizll; 2.5, respectively.

The front wall of the pump". casing comprises a flat main sectionzowhich is -g'enerallyfof disk formtand secured at itsedge to the front"coupling flange '22 of the peripheral wall of the :pres sure:- chamberand is'provi'dedat one part of its. peripheral edge with'atangentiallcheek 21 of 'flat' form extending: across thespace between:the*outer: and inner wings or spout walls 20, 21 and secured to thefrontflanges'fliof these wings. The'main dislr section :265of: the-frontcasingswall and its tangential cheek 21 are preferably formed integrallyfrom a Single plate or sheet of weldable metal.

The edge of the front casing wall is detachably connected with the frontcoupling flanges 22 of the peripheral wall by means of bolts 28, and theopposite edges of the cheek 21 are likewise connected with thecorresponding coupling flanges 24, 24 at the front edges of thelongitudinal wings or walls 28, 2| of the discharge spout I8 by means ofbolts 29.

Axially in line with the driving shaft the disk section 25 of the frontcasing wall is provided with an opening 30 in which the rear end of ametal tube 3| is secured by welding 32, this tube forming the main partof the eye or inlet I! through which the fluid to be pumped is conductedinto the pressure chamber of the pump. At its front or outer end thismetal inlet tube has secured to its periphery by welding 33 a couplingflange 34 of metal whereby the inlet tube of the casing is coupled withsuitable piping through which the liquid to be pumped is supplied to thecasing.

For the purpose of maintaining the front wall of the casing in a flatcondition and preventing the same from being distorted by pressurewithin the casing, means are provided for strengthening the same, thisbeing preferably accomplished by a plurality of radial stiffening orreinforcing ribs 35 which are secured to the outer side of the frontcasing wall 26 and to the adjacent external surfaces of the inlet tube3| and its coupling flange 34 by means of welding. These stiffening ribsare also constructed of strips of flat metal which have been rolled andcut into the required shape.

The rear side wall of the casing of the pressure chamber and itsdischarge spout are also constructed from a single sheet of plate metalwhich has been rolled and cut into shape so as to form a main disksection 36 which is arranged transversely in rear of the peripheral wallIQ of the casing and a tangential cheek or section 3'! which extendstransversely across the rear edges of the longitudinal walls or wings20, 2i of the discharge spout !8. The driving shaft extends through thecentral part of this disk of the rear wall and is operatively connectedat its front end with the impeller which is arranged within the pressurechamber of the casing. The edge of the disk of 'the rear wall isconnected by bolts 38 with the rear coupling flange 23 on the peripheralwall of the casing and the transverse cheek 31 of this rear wall is alsoconnected by means of bolts 39 with the flanges 25, 25 on the rear edgesof the longitudinal walls or wings 20, 2! of the discharge spout oroutlet, as shown in Figs. 2, 4 and 6. 1 The numeral 40 represents tiebolts passing through the edges of the disks 25, 36 of the front and'rear' casing walls and the flanges 22, 23 of the peripheral orcircumferential wall l9 of the case and having the heads and nuts atopposite ends of the bodies of these bolts bearing, respectively,against the outer sides of these walls for the purpose of tying theseveral walls of the casing firmly'together, as shown in Fig. 3.

In its central part the disk section of the rear casing wall is providedwith an opening M in which is secured, by Welding 42, a tubular neck43of weldable metal which is axially in line with the driving shaft andsurrounds the adjacent portion of the same and forms partof the casing..The numeral M represents an annular head secured at its periphery bywelding 45 to the rear end f the casing neck 43 while its central partis provided with an opening 45! for the passage of the adjacent part ofthe driving shaft, as shown in Fig. 3. This casing head 44 together withthe casing neck 43 form a recess or pocket 46 on the inner side of therear casing wall which opens into the pressure chamber and is adapted toreceive part of the hub 61 of the impeller.

On the outer side of the casing head a stuffing box is mounted whichreceives a packing and the adjacent part of the driving shaft and formsa joint therebetween for preventing leakage from the interior of thepressure chamber to the exterior of the same. This stuffing box, as bestshown in Fig. 3, comprises a housing tube 41 of sheet metal surroundingthe driving shaft and having its front end secured by welding 48 to theouter side of this head 44 and having its bore spaced from the peripheryof the driving shaft so as to form an annular packing spacetherebetween, and an outwardly facing internal shoulder .9 on the outerside of the head 44, as shown in Fig. 3. The tube 41' isfilledwithalubricating packing 5!! of any suitable character and this ispressed inwardly toward the shoulder 49 by a gland 5| projecting intothis tube and held in place in any suitable manner.

Strengthening of the rear casingwall, for the purpose of preventingpressure within the chamber it from distorting this wall, is preferablyaccomplished by means of a plurality of stiffening or strengthening ribs52 of flat metal arranged radially around the outer side of the rearcasing wall 36 and secured by welding to the outer side of this rearwall and the adjacent part of the casing neck 43 and the casing head 44,as shown in Fig. 3.

Various means may be employed for mounting the casing of the pump on themain frame but those shown in the drawings are preferred and constructedas follows:

The numeral 53 represents a supporting ring of weldable metal which isarranged concentrically around the driving shaft and associated partsand is secured by welding 54 to the several ribs 52 of the rear casingwall plate. This supporting ring together with the pump casing isdetachably connected with the main frame of the pump by engaging thelower edge portion of the supporting ring 53 with a semi-circular seator shoulder 55 on theiront part of the main frame and detachablyconnecting this ring with the respective part of the main frame by aplurality of bolts 56, as shown in Figs. 1, 3 and 5. By these means thepump casing can be readily mounted on the main frame when originallyinstalled and also quickly removed therefrom for inspection, adjustmentand repairing whenever this is required. The supporting ring 53 isreinforced by stiffening ribs 51 of metal secured to the outer side ofthis ring by welding.

Means are provided which embody this invention whereby the tangentialoutlet or discharge spout [8 of the pressure chamber is connected with adelivery piping or conduit for carrying the liquid which has been pumpedto the desired destination. The preferred means for this purpose whichare shown in Figs. 1, 2 and 4 are constructed as follows:

The numeral 15 represents an annular coupling flange which has its innerside secured by Welding to the outer edges of the transverse walls 21,3'! and the longitudinal walls 20, 21 of the delivery spout l8, thiscoupling ring being also connected :by welding tometai brackets 58 whichare welded to the outer side of the transverse walls 21,31.

The numeral 59 represents an adaptor tube which may formzpart'ofthepiping whereby the tube and the coupling flange l5whic-h ispermanently connected with the discharge-spout.

- The impeller whereby-the'fluidto be pumped is drawn into the" casingthrough the inlet eyell of the same and discharged through-thetan-.gential outlet I8 thereof may be variously congstructed, that formshownin Figs. 2; 3=and 4 being constructed as follows:

The numeral 67 represents thehub of theimpeller which is'provided with aconical bore engaging with-the conical front end of. the" driving.shaft'and held thereon by aretaining nut 68 screwed onto the drivingshaft and bearing against the inner end-of this hub-. From the'.

and rear shrouds.

' The numeral H represents a plurality of curved impeller vanes orblades which extend across the space'between'thefront'and rear shroudsand are preferably integrally connected therewith. As this impellerrotates in the direction of the arrow indicated in Fig. 4, the liquid inthe pump isd'rawn through the inlet eye 11 into the space between theshrouds of the impeller and then this liquidis rotated inthe pressurechamber and discharged therefrom through the tangential outletthereofina manner common to this type of pump.

In order to protect the internal surfaces or parts of the pump againstwearand-corrosion when the same is utilized for pumping; liquidscontaining abrasive materials or chemicals which 'havea destructiveeffect on iron or'steel'; of which the main parts of the pump areconstructed, the inner surfaces of the pump are provided with protectivelinings or coverings of-a character which will resist'wear or. corrosiondependingup'onthe character of the material which is being pumped.

The means for thus protecting the internal surfaces of the pump againstwear or corrosion are constructed as follows:

The numeral 6! represents a protecting lining section having the form ofa fiat disk which is secured to the inner side of the front casing wall26 and provided centrally with a forwardly projecting protecting liningtube 62 which is arranged in the bore of the inlet tube 3! of thecasing. At its periphery this lining disk BI is provided with atangential protecting tab 63 which covers the inner side of thetangential cheek 21 forming the front wall of the discharge spout I8.The edges of the lining disk GI and the lining tab 63 are arrangedbetween the flanges 22 and 24 on the front edges of the cylindricalcasing wall It and its wings 20, 2| and these members are connected bybolts 28, 29, whereby these parts of the lining also form gaskets orpackings and produce a tight joint between the respective parts of thecasing.

The numeral 64 represents the fiat disk section '6 ofa-iprotectingllming secured to the inneri'side of the rear casing'wa1l'36and provided centrally withiarearwardlyprojecting tube 65which'is arranged'iin' the bore of the tubular neck 43 soas to formaprotecting, lining therefor.

At one part of its peripheral'edge the rearlining disk" 64'is providedwith a tangential tab 66 which extends across the flanges 25, 25 on therear edges'cr the Wings 20; 2i of the discharge spout and form's'aprotecting lining for the rear cheek 31 of the rear casingwall 36. Theedge portions of the disk 64 and its tangential tab Stare arranged;respectively, between the flanges 23, 25 -011 the rearedges-of'thecylindrical wall section l-e and its wings 20, 2l'andthe edges of therear wall disk 36 and its. cheek 3'! and clamped between the same bybolts 49, 39 so that the liningsections 64, 136 serveasa gasket betweenthe respective parts of the pump casing whereby leakage from theinterior of the pressure chamber-to the exterior of the pump isprevented.

The numeral 76 represents a protecting lining section having the form ofa split cylinder and covering the inner side of theoylindricalperipheral 'wall I9 of the casing'and having its ends onopp'ositesidesof its splitpart provided with inner-and outertangential flaps .11,18 which are arranged lengthwise and cover the inner sides of thelongitudinal wings 20', 2| of the casing outletspout l8, as shown inFig. 6; The cylindrical lining section IS-engages its front and rearedges withinner opposing sides of'the marginal parts of'the front andrear protecting disk lining-sections 61; 64, shown in Fig. 3, and thefront and' rear edges ofthe innerand outer lining fiaps l'l, 18 0f thiscylindrical lining-section engage Withthe vertical edge portions ofthe'fron't andrear lining tabs 63. 66 of the outlet'spout I8, as showninFig; 6.-

By these means virtually the entire inner surfaces of the casingare-covered with protecting material; I

When this pumpis used for propelling liquids of an abrasivecharacterthese lining members are preferably constructed of rubber or similarresilient'material which iswear resistant and when rubberis used as aprotecting lining these several members are connected with respectivemetal parts of the pump by vulcanization. When, however, this lining iscomposed of material which is intended to' render the internal surfacesof the'pump" corrosion resistant these protecting members may beconstructed of lead or other metal or material best suited to theparticular liquid which is being pumped. Metallic linings may be securedto the inner surfaces of the respective pump members by Welding or anyother suitable method.

For the purpose of protecting the main surfaces of the impeller whichcome into immediate contact with the liquid which is being pumped andthereby save them from undue wear or corrosion the following means areprovided:

The numeral 12 represents a protecting covering of rubber or equivalentmaterial which completely covers or envelopes the opposite flat sidesand edges of front shroud 10, as shown in Fig. 3.

Each of the impeller blades or vanes H is completely covered on itsopposite curved sides and on its edges by a protection coverin 14 ofrubber or the like, as shown in Figs. 3 and 4.

The rear shroud 69 of the impeller is protected by a covering of rubberor similar material which comprises an inner disk shaped lining section13 secured to the inner side of the rear shroud and provided centrallywith an opening 75 through which the front end of the drivingshaftprojects, an outer disk shaped lining section 16 secured to the outerside of the rear shroud and connected at its peripheral edge with thecorresponding edge of the inner lining section by a web 90 extendingover the peripheral edge of the rear shroud, and a tubular collar 9|projecting rearwardly from the central part of the outer lining section16 and secured to the periphery of the impeller hub 61.

At its front end the hub of the impeller is pro- 'vided with an annularshoulder or rabbet 92 and the peripheral part of this nut bears againstthe inner edge portion of the lining section- 13 around the centralopening 15 thereof "and presses same firmly against the impeller hub,.as shown in Fig. 3. I I

As a whole the several parts of this pump are extremely light therebypermitting the same to be easily handled for transportation and forlining and relining. The interior of" the pump is readily accessible forlining or relining and also enables a beter and more reliable bond to beobtained between the lining sections and the :metal members of the pumpto which they are :attached. Inasmuch as most of the several members ofthis pump are made of sheet metal, such as steel or an alloy, thesemembers can be economically pie-fabricated by cutting or stamping,thereb eliminating the high costs attending the manufacture of pumps asheretofore constructed and also permitting of readily applying naturalrubber or synthetic rubber to those surfaces which are engaged b thestream of liquid which is being pumped. Moreover, by making the mainparts of this pump of sheetlike or rolled metal, comparatively smoothsurfaces are presented on the inner side of the pump for attachment ofthe protecting linings thereto which can be accomplished more readilythan attaching such linings to the rough surfaces of castings.

The use of sheet metal for making the major parts of this pump insteadof using castings has the further advantage that it eliminates to a verylarge extent machine work which is required 8 when making parts of castiron as has been the practice heretofore.

I claim as my invention:

A centrifugal pump comprising a casing containing a pressure chamber, anaxial inlet on one side of said chamber and a tangential outlet on theperiphery of said chamber, and an impeller rotatable in'said chamber;said casing including a split cylindrical section forming a peripheralwall of said pressure chamber and two wings at opposite ends of thecylindrical section and forming the longitudinal walls of said outlet, afront transverse wall plate having a front main disk section secured atits edge to the front edge of said cylindrical section and forming thefront wall of the pressure chamber, and a tangential front cheekarranged on the edge of said front disk section and secured to the frontedges of said wings and forming the front wall of said outlet, a reartransverse wall plate having a rear main disk section secured at itsedge to the rear edge of said cylindrical section and forming the rearwall of the pressure chamber, a tangential rear cheek arranged on theedge of said rear disk and secured to the rear edges of said wings andforming the rear wall of said outlet, stiffening ribs secured to theouter side of said rear wall disk section, a main frame having a seat,and means for mounting said casing onsaid frame including a supportingring secured permanently to said stiffening ribs 'and engaging saidseat, and bolts detachably connecting said supporting ring with saidframe.

' WILLIAM H. PFARRER.

REFERENCES CITED I The following references are of record in the file ofthis patent:

